Re: Deleting a certain part of the navigation
I believe you can put it in /plugins/bp-custom.php (create the file if it doesn’t exist already). This is rough code, but I’m assuming you’ll want to do it like this:
function remove_navitems()
{
bp_core_remove_nav_item('blogs');
}
add_action('bp_core_setup_nav', 'remove_navitems');
At a first glance, that is what I’d try. Not sure if it’ll work, but that should get you going in the right direction.